Milk is a food with all kind of nutrition. However, many cows have mastitis, the rate is high. Normally, milkers use antibiotics for treating mastitis. Therefore, the amount of rudimental antibiotics in milk is considerable. Human drinking milk having the rudimental antibiotics long term will cause accumulation of antibiotics in body, it results human-body physiological disorder and drug resistance to the antibiotics. Consequently, the milk with rudimental antibiotics is a kind of food pollution, which damages human health. To cue the damage from milk with rudimental antibiotics is more difficult than to rule the environment pollution. The best way to deracinate the damage is treating the mastitis by using less or no antibiotics. Thereby, people expect a kind of health protection device for udders of cows to replace the antibiotics for cow's mastitis. Chinese patent No. 85204929 disclosed a “Brassiere Diminishing Inflammation for Cows with Rare-Earth Permanent Magnet”, which is a safe, simple and effective tool for treating mastitis, but it has single function only, needs manual operation, operates inconveniently and is not easy to be popularized.